zrepl/internal/platformtest/platformtest_zpool.go
2024-10-18 19:21:17 +02:00

130 lines
3.4 KiB
Go

package platformtest
import (
"context"
"fmt"
"os"
"path/filepath"
"runtime"
"strings"
"time"
"github.com/pkg/errors"
"github.com/zrepl/zrepl/internal/zfs"
)
var ZpoolExportTimeout time.Duration = 500 * time.Millisecond
type Zpool struct {
args ZpoolCreateArgs
}
type ZpoolCreateArgs struct {
PoolName string
ImagePath string
ImageSize int64
Mountpoint string
}
func (a ZpoolCreateArgs) Validate() error {
if !filepath.IsAbs(a.ImagePath) {
return errors.Errorf("ImagePath must be absolute, got %q", a.ImagePath)
}
const minImageSize = 1024
if a.ImageSize < minImageSize {
return errors.Errorf("ImageSize must be > %v, got %v", minImageSize, a.ImageSize)
}
if a.Mountpoint == "" || a.Mountpoint[0] != '/' {
return errors.Errorf("Mountpoint must be an absolute path to a directory")
}
if a.PoolName == "" {
return errors.Errorf("PoolName must not be empty")
}
return nil
}
func CreateOrReplaceZpool(ctx context.Context, e Execer, args ZpoolCreateArgs) (*Zpool, error) {
if err := args.Validate(); err != nil {
return nil, errors.Wrap(err, "zpool create args validation error")
}
// export pool if it already exists (idempotence)
if _, err := zfs.ZFSGetRawAnySource(ctx, args.PoolName, []string{"name"}); err != nil {
if _, ok := err.(*zfs.DatasetDoesNotExist); ok {
// we'll create it shortly
} else {
return nil, errors.Wrapf(err, "cannot determine whether test pool %q exists", args.PoolName)
}
} else {
// exists, export it, OpenFile will destroy it
if err := e.RunExpectSuccessNoOutput(ctx, "zpool", "export", args.PoolName); err != nil {
return nil, errors.Wrapf(err, "cannot destroy test pool %q", args.PoolName)
}
}
// clear the mountpoint dir
if err := os.RemoveAll(args.Mountpoint); err != nil {
return nil, errors.Wrapf(err, "remove mountpoint dir %q", args.Mountpoint)
}
if err := os.Mkdir(args.Mountpoint, 0700); err != nil {
return nil, errors.Wrapf(err, "create mountpoint dir %q", args.Mountpoint)
}
// idempotently (re)create the pool image
image, err := os.OpenFile(args.ImagePath, os.O_CREATE|os.O_RDWR, 0600)
if err != nil {
return nil, errors.Wrap(err, "create image file")
}
defer image.Close()
if err := image.Truncate(args.ImageSize); err != nil {
return nil, errors.Wrap(err, "create image: truncate")
}
image.Close()
// create the pool
err = e.RunExpectSuccessNoOutput(ctx, "zpool", "create", "-f",
"-O", fmt.Sprintf("mountpoint=%s", args.Mountpoint),
args.PoolName, args.ImagePath,
)
if err != nil {
return nil, errors.Wrap(err, "zpool create")
}
return &Zpool{args}, nil
}
func (p *Zpool) Name() string { return p.args.PoolName }
func (p *Zpool) Destroy(ctx context.Context, e Execer) error {
exportDeadline := time.Now().Add(ZpoolExportTimeout)
for {
if time.Now().After(exportDeadline) {
return errors.Errorf("could not zpool export (got 'pool is busy'): %s", p.args.PoolName)
}
err := e.RunExpectSuccessNoOutput(ctx, "zpool", "export", p.args.PoolName)
if err == nil {
break
}
if strings.Contains(err.Error(), "pool is busy") {
runtime.Gosched()
continue
}
if err != nil {
return errors.Wrapf(err, "export pool %q", p.args.PoolName)
}
}
if err := os.Remove(p.args.ImagePath); err != nil {
return errors.Wrapf(err, "remove pool image")
}
if err := os.RemoveAll(p.args.Mountpoint); err != nil {
return errors.Wrapf(err, "remove mountpoint dir %q", p.args.Mountpoint)
}
return nil
}